First pass implementation of jobs system.
Merge branch 'dev' of https://github.com/HaxeFlixel/flixel into dev

Conflicts:
	flixel/FlxG.hx
Merge branch 'dev' of https://github.com/HaxeFlixel/flixel into dev

Conflicts:
	flixel/FlxObject.hx
Fixing dev branch oopsies.
Support more of FlxSprite's properties in FlxSpriteGroup
made SoundFrontEnd.play() return a FlxSound also on android instead of null, allowing to modifying the sound later on (for example to restart it for seamless audio loops
Merge branch 'dev' of https://github.com/HaxeFlixel/flixel into dev_FlxSpriteGroup

Conflicts:
	flixel/group/FlxSpriteGroup.hx
Update FlxSpriteGroup to include both the changes to add() and the new properties
Merge branch 'dev' of https://github.com/HaxeFlixel/flixel into dev_FlxSpriteGroup

Conflicts:
	flixel/group/FlxSpriteGroup.hx
Merge remote-tracking branch 'origin/dev' into dev
animation refactoring
forgot upload new classes :)
Fix debugger pause
forgot to update FlxObject class, sorry again
init new Debugger FlxSystemButtons
Merge remote-tracking branch 'origin/dev' into dev
Merge branch 'dev' of https://github.com/HaxeFlixel/flixel into debugger_buttons
Refactor VCR and VCRFrontend, pause, resume, step does not require the debugger enabled anymore. Uses the new Fluid layout and system buttons.
some fixes regarding animation refactoring
some more animations fixes